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In practice, what are the main uses for the new “yield from” syntax in Python 3.3?
...ld from is all about. Because, let's face it, if all yield from does is expand the for loop, then it does not warrant adding yield from to the language and preclude a whole bunch of new features from being implemented in Python 2.x.
What yield from does is it establishes a transparent bidirectional...
Finding current executable's path without /proc/self/exe
...ecutable or a name that was found using $PATH.
Some shells, including bash and ksh, set the environment variable "_" to the full path of the executable before it is executed. In that case you can use getenv("_") to get it. However this is unreliable because not all shells do this, and it could be ...
How to compare two floating point numbers in Bash?
...) )); then
…
fi
Explanation
Piping through the basic calculator command bc returns either 1 or 0.
The option -l is equivalent to --mathlib; it loads the standard math library.
Enclosing the whole expression between double parenthesis (( )) will translate these values to respectively true or...
Which terminal command to get just IP address and nothing else?
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It says that -i and -I are both illegal options
– Mason
Dec 16 '11 at 3:08
3
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How can I profile Python code line-by-line?
I've been using cProfile to profile my code, and it's been working great. I also use gprof2dot.py to visualize the results (makes it a little clearer).
...
Android emulator shows nothing except black screen and adb devices shows “device offline”
I am just trying to start development in Android.
So, the problem is that when I try to launch an emulator by issuing the command emulator @A2 , an emulator comes up on the screen. But even after waiting for as long as 2-3 hrs, all it shows is a black screen. Not even the android home screen or t...
Is floating point math broken?
...is like this. In most programming languages, it is based on the IEEE 754 standard. The crux of the problem is that numbers are represented in this format as a whole number times a power of two; rational numbers (such as 0.1, which is 1/10) whose denominator is not a power of two cannot be exactly re...
Limit file format when using ?
...I'd like to know if there is a solution. I'd like to keep solely to HTML and JavaScript; no Flash please.
11 Answers
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What is the 'pythonic' equivalent to the 'fold' function from functional programming?
...u can sometimes use some combination of reduce (from the functools module) and the operator module, e.g.:
def product(xs):
return reduce(operator.mul, xs, 1)
Be aware that reduce is actually a foldl, in Haskell terms. There is no special syntax to perform folds, there's no builtin foldr, and ...
Disable browser's back button
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Do not disable expected browser behaviour.
Make your pages handle the possibility of users going back a page or two; don't try to cripple their software.
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